Apparatus for manufacture of paint brushes



Oct. 27, 1964 A. J. ANDERSON 3,154,345

APPARATUS FOR MANUFACTURE OF PAINT BRUSHES Filed June 18, 1962 INVENTOR ALFRED J. ANDERSON ATTORNEYS dy w United States Patent 3,154,346 APPARATUS Fit-R MANUFAQ l Eli-til 8F PAINT ERUSEES Alfred J. Anderson, Livingston, Ni, assignor to H. V. Hardman Company line, a corporation of New Jersey Filed June 18, 1962, Ser. No. 2%,117 11 Claims. (Ci. 3430-2) The present invention relates to a continuous process for the manufacture of paint brushes.

In accordance with the present invention bristles are sized out in a ferrule in conventional manner and then the ferrule with the bristles therein are continuously loaded on a conveyor which carries the ferrules through a first station where a measured amount of liquid cement is automatically injected into the ferrule to form a pool on top of the bristle knot in the ferrule. After this is done the ferrules are automatically conveyed through a second station where handles are inserted in the top of the ferrule and pushed down into the pool of cement. The brush assembly is then conveyed through a third station where the cement is cured and hardened to complete the brush which is thereafter automatically discharged from the conveyor ready to be packaged and shipped.

In the continuous process of the present invention many operations heretofore carried out by hand are automatically performed which greatly speeds up production and reduces manufacturing costs. It only takes about fifteen minutes to produce a finished brush and thirty brushes have been made in one minute in a preferred form of apparatus illustrated in the drawings. Distribution of the cement employed for anchoring the handle and bristle knot in the ferrule is automatically controlled to insure uniform product of optimum strength.

Other advantages and the details of the continuous process of the present invention are best understood by reference to the preferred form of apparatus illustrated in the drawings in which:

FIG. 1 is a schematic presentation of a preferred form of equipment which may be utilized to carry out the process of the present invention.

FIG. 2 is a section taken along line 2-2 of FIG 1.

In the drawings, a conveyor 19 is preferably driven by an intermittent drive mechanism 12. The conveyor is a continuous link chain 1 which is stretched around two horizontally disposed sprockets with gear teeth that mesh with the links of the chain 14. The teeth on one of the sprockets hereinafter referred to as the conveyor drive sprocket 16 also mesh with a second continuous link chain 18. This second chain is stretched around two more horizontally disposed sprockets 2t and 22, one of which is driven by the output shaft 24 of the intermittent drive mechanism 12. The other conveyor sprocket 26 is an idler sprocket which rotates freely with the link chain 14 as the chain moves around it. Therefore, as the output shaft 24 of the intermittent drive mechanism 12 moves its motion is transmitted to tie conveyor drive sprocket 14 by the second continuous link chain 18. The drive sprocket, in turn, transmits the motion to the conveyor link chain 14 which then moves around the conveyor drive and idler sprockets 16 and 25 with the motion of the intermittent drive mechanism 12.

The intermittent drive mechanism 12 includes a Geneva type movement with a star wheel 23 which is coupled to the output shaft 24 and provided with a number of arcuate concavities 30 separated by radial slots 32. Motion of the star wheel 28 is controlled by a crescent shaped stop 34 and an indexing pin 35 driven by the output of a reduction gear box 37. The gear box in turn is driven by electric motor 38 which transmits power to the gear box 37 through a belt drive 4t 3,154,345 Patented Get. 27, 1964 "ice A switch 46 is connected in series between the A.C. lines and the motor 38 to stop and start the motor. When switch 46 is closed the electric motor 33 drives gear box 37 which transmits the motion to the crescent shaped stop 34 so that the convex surface 48 of the stop slides in one of the concavities 36 of the star wheel 28. As a result the output shaft 24 of the drive mechanism is held stationary. The shaft 24 remains stationary until the stop 34 rotates out of the concavity 3t) and the index pin 36 moves into one of the slots 32 whereupon the pin moves the star wheel 28 by exerting pressure on the side wall of the slots. The movement of the star wheel continues until the pin 36 leaves the slot 32 whereupon the convex surface 48 of the stop 34 enters another of the concavities 30 of the star wheel 28 to hold it stationary. Therefore, the Geneva movement moves the shaft 24 with a stop motion as the motor 33 rotates. The shaft is stationary while the convex surface 48 slides in the arcuate concavities 3i? and rotates as the indexing pin 35 moves in the radial slots 32. This stop motion is transmitted by conveyor drive sprocket 16 to the conveyor chain 14 so that the conveyor chain moves around the conveyor sprockets 16 and 25 with alternating periods of rest and motion. These periods are arranged in a two second cycle with the conveyor chain 14 remaining stationary two thirds of the time and moving for one third of the time. While the form of conveyor illustrated in the drawings gives best results it will be understood that conventional forms of conveyors may also be employed in carrying out the process of the present invention.

Extending out from the conveyor at fixed intervals around the continuous chain 14 are a number of clamps 59. These clamps are adapted to grasp the exterior surface of the ferrules 52 so that the bristles 54 hang freely from the ferrules and the clamps do not obstruct the open end 56 of the ferrule. Only those clamps necessary to clearly illustrate operation of the device are shown in PEG. 1. The addition of more clamps would not serve any useful purpose and would unnecessarily clutter the drawing.

Referring to FIG. 2 the clamps consist of a movable jaw 57 and a fixed jaw 58. The arm 69 of the movable jaw passes through openings 62 in a guide 64 that is fixedly secured to the fixed jaw 58 so that the arm 6% may move back and forth through the guide to open and close the jaws 57 and 58. A jaw spring 66 is placed around the end portion of the jaw arm 60 extending through openings 62 in the guide 6 This spring is held between the jaw arm guide 64 and a washer 66 by a cotter pin 79 which holds the washer in position against the spring. The spring forces the washer away from the guide against the cotter pin 7tl so that with the spring 66 in its expanded position the jaws 57 and 58 of the clamp are closed.

To hold the jaws open a catch 72 is provided. This catch is adapted to enter one of a number of indentations '74 in the jaw arm to hold jaws 5'7 and 58 open by keeping the jaw arm spring 65 compressed. The catch is pivotly mounted on the fixed jaw 56 of the clamp and extends through an opening 75 in the jaw arm guide to engage the indentations 74. The catch has a spring 76 which presses it against the movable jaw arm 58 so that as the jaws open, the catch rides along the surface of the movable jaw arm 58 following the indentations 74 therein. When the jaws start to close the spring 76 forces the catch into the first indentation it passes over preventing any further movement of the movable jaw 57. To release the catch a pressure plate 78 is provided which compresses the catch spring 76 and pivots the catch 72 away from the movable jaw arm 60 out of the indentation 74- so the movable jaw arm slides freely through the guide holes 62 as the jaws are closed by the force of the jaw arm spring 66. When a ferrule is inserted into the clamp it contacts the pressure plate 78 causing the jaws 57 and 58 to close around the ferrule and hold it. A piece of elastomer tubing St is placed around the movable jaw to absorb the shock of the closing jaws so that the unglued bristles are not dislodged from the ferrule.

While the described form of clamp is especially adapted for use in carrying out the process of the present invention a conventional type of clamp may be employed. For example an ordinary spring clip may be used to grasp the exterior side wall of the ferrule.

After the ferrules are inserted into the clamps, each clamp 50 is carried by the continuous link chain 14 into the first station underneath a pump 82. The clamps each stop directly under the nozzle 84 of the pump, as a result of the stop motion of the conveyor chain 14, so the pump may dispense a measured amount of cement into each ferrule. The pump is preferably of the type described in my co-pending application Serial No. 48,005, filed August 8, 1960 for Proportioning Apparatus. This pump mixes, measures and dispenses in varying selected proportions two difierent viscosities of the resin and a catalyst for the resin. An adjustment in the pump permits an operator to change the viscosity of the cement by varying the proportions of the two different resins so that the penetration of the cement into the bristles may be controlled. In addition, the amount of cement dispensed into the ferrule is also controlled by an adjustment in the pump. Any conventional pump adapted for intermittent operation to deliver a measured shot of liquid cement may be employed such as for example described in United States Patent No. 2,895,644.

Any conventional liquid cement may be employed in the process of the present invention but the selected cement must be substantially free of solvents. This is important because as described hereinbelow the cement is cured and hardened after the handle is inserted into the top of the ferrule. As a result any appreciable expansion or contraction of the liquid cement caused by evaporation of solvent would tend to disrupt the assembly and interfere with the proper distribution of the cement for anchoring'the bristle knot and handle in the ferrule. In those cases where a plastic handle such as polyethylene or synthetic bristles such as nylon are employed, the selected cement must be one that is capable of being cured and hardened at temperatures below the softening point of the plastic material in the brush and preferably the cement is one which will cure and harden at atmospheric temperature and pressure. Examples of liquid cements which have been employed with excellent results include the liquid epoxy resins, liquidphenolic resins, resorcinol aldehyde resins and polyester resins. All of these as well known in the art may be cured at atmospheric temperatures and pressures with conventional catalyst employed for this purpose.

In order to synchronize the dispensing of cement from pump 82 with movement of ferrules 54 a microswitch 86 which controls the pump 82 is positioned adjacent pin 36 in the intermittent drive mechanism 12. As a ferrule is moved into the first station under the nozzle of pump 82, the pin 36 contacts the micro-switch 86 which is thereby closed to actuate the pump which delivers a predetermined quantity of liquid cement into the ferrule on top of the bristle knot each time the switch is closed. Since there may not be a ferrule in each of the clamping positions on the conveyor a photosensitive switch 88 is positioned in the pumping station where the beam of light to the switch will be interrupted each time a ferrule is moved into position to receive a measured amount of liquid cement. The photosensitive switch 88 assures that the pump will only be actuated to dispense cement when a ferrule is positioned under the nozzle of the pump.

After the ferrules receive cement they are conveyed into the second station where handles are inserted into the ferrules. The insertion of handles may either be done by hand or by an automatic device described herein. As shown handles 94 are stored in a handle magazine 96 positioned above the continuous chain 14. The handles are forced toward one end 97 of the magazine 96 by a spring loaded plate 93. Suspended above end 7 of the magazine by any convenient means is a solenoid operated plunger 10%). The solenoid of this plunger may be activated in the same manner as that employed for pump 82, that is an electric eye and micro-switch as shown at 88 and 35 respectively may be used in conjunction with the plunger to coordinate the dispensing of the handles 94 with the position of the ferrules 52. When a ferrule stops underneath the end 97 of the handle magazine 96, the electric eye and the micro-switch close the circuit between the solenoid of the plunger and the excitation for the solenoid. With the closing of the two switches the plunger forces a handle down through a hole in the magazine 96 and into the ferrule below the hole. Pressure exerted on the remaining handles by the spring loaded plate 98 moves the handles toward the end of the magazine to fill the void left by the handle that was forced through the hole.

When the handle is inserted into the ferrule a support (not shown) is preferably moved in under the ferrule to provide positive support. If such support is not employed the force of the plunger or the force exerted by the operator in putting the handles into the ferrules should not be too great because there is danger that the brush assembly may be dislodged from the clamp.

A preferred form of brush structure is made by using the hollow plastic handles disclosed in patent application Serial No. 6,244 filed for Brush Structure and Methods for Assembling Same. It will be noted that in the preferred form of process a handle is inserted into a ferrule at the same time that a different ferrule receives a shot of cement.

With the handles in the ferrule the brush structure is now complete. However, it is still necessary that the cement harden to bind the bristles, handle and ferrule. If desired this may be done by letting the cement cure and harden at atmospheric pressure and temperature. However, we achieve a much more uniform structure and a higher rate of production by accelerating the cure with heat. For this purpose the brush is passed into a third station comprising a hood 162 where warm air is blown across the ferrules to heat them and accelerate hardening of the cement. As the brush moves along under hood 102 the warm air alternately passes across the ferrule in one direction and then in the other. This change in direction of air preferably occurs four times which insures even heating on both sides of the ferrule and an even cure of the resin. The air for this operation comes from a pump (not shown) and is transmitted to ducts 194 on the sides of the hood by pipes 106. The air passes over fin heaters 108 within the ducts, which heats the air as it passes over the fins.

When the brushes emerge from the hood the cement is hard and the finished brushes may be removed from the conveyor belt either by hand or automatically by mechanical means. The brush making cycle takes about ten minutes and finished brushes may be removed from the conveyor at rates up to forty brushes a minute. Since the brush may be completed in ten minutes, a test brush may be readily run through the brush making cycle and then examined to check the penetration of the cement into the bristle knot. Pump 82 may then be adjusted to deliver the proper viscosity of cement for the desired penetration and bond to the handle.

As for removing the completed brushes from the conveyor by mechanical means, a rod 110 is provided for releasing the ferrules from the jaws 57 and 58. The rod 11% contacts the extending end of the movable jaw arm 6d of the clamp 56 to compress the jaw arm spring 66 and open the jaws. As the spring is compressed the arm 60 moves relative to the jaw arm guide with the catch arm 72 riding freely over the indentations 74 in surface of the arm 60. After the release of the brush the rod 110 reverses its direction removing the force from the end of the jaw arm 60. The jaw arm 60 forced by the spring 66 tends to follow this movement until the catch 72 enters an indentation 74 whereupon the catch stops the motion of the arm, holding the jaws 57 and 58 open and the jaw arm spring 66 in compression. The jaws are opened sufiiciently for the insertion of another ferrule so a new brush making cycle may be started. In this connection it should be understood that the opening of the jaws should not be excessive. If the jaws are opened excessively the force exerted by the clamping of the jaws to the ferrule will cause bristles to be jarred from the ferrule. The rest position of the rod 119 is adjustable to permit correct opening of the jaws for the size brush at hand.

To drive the rod 110 power is transmitted from the gear box 32 to a cam 114 attached to the output of the gear box 28. As the motor 28 rotates this cam 114 contacts an extending end 116 of a moment arm 118. This pivots the moment arm around pivot point 12% causing the arm to pivot back and forth in an are around point 126 as the motor 38 rotates. A pin 122 riding in a slot 124 in the arm 1218 transfers this motion to shaft 126 causing the shaft to oscillate back and forth along its longitudinal axis. The other end of the shaft 126 has gear teeth which mesh with a pinion gear 128, to transfer to the pinion gear the motion of the shaft 126. A second pinion gear 130 axially aligned with the first pinion gear 128 transmits the back and forth motion to the rod 116.

When the completed brush is released by the jaws it slides down a ramp 132 onto a conveyor belt 134 and is transported to bristle trimming areas. It will be noted that in the preferred process removal of the finished brush from the conveyor takes place simultaneously with the operations performed in the three stations described hereinabove.

To recapitulate, the electric motor 38 through Geneva drive 12 drives the continuous link chain 14 with a stop go motion around the sprockets 16 and 26. The clamps 5i) that are attached along the length of the continuous link chain 14 move with the chain around the sprockets. As each clamp 50 passes rod 110 it stops in front of it and the rod contacts the end of the movable jaw arm 60 of the clamp forcing the jaws 57 and 58 open. When the force exerted by the rod 110 on the arm 69 is released the catch 72 enters one of the indentations 74 holding the jaws open. As the clamps continue to move along on the conveyor belt an operator inserts a ferrule 52 with the bristles 54 therein between the jaws of the clamp pressing the ferrule up against the touch sensitive plate '74 of the catch. This releases the catch causing the jaws 56 and 58 of the catch to clamp the ferrule between them.

With the ferrule in it each clamp stops under the pump 32 and therefore intercepts the light beam on the photo cell 92. While the clamp is stopped under the pump, pin 36 contacts the roller arm of the micro-switch 86 to cause pump 82 to dispense a measured shot of cement into the ferrule.

The clamp is then carried by the conveyor belt under the handle plunger 100. The plunger drops a handle down into the ferrule. It should be pointed out at this time that some of the cement dispensed by the pump forms a pool on top of the bristles. The skirt of the handle enters this pool for the purpose of locking the handle to the ferrule. The amount of cement dispensed by the pump should be suflicient to leave enough cement on top of the bristles after the curing of the cement, to form a solid connection between the handle and the cement. In the above mentioned patent application Serial No. 6,244 in one form of the handle disclosed therein the bottom edge of the skirt has holes in it into which the cement enters to form bridges that securely lock the handle in the ferrule when the cement hardens.

The assembled brush structure is then carried by the conveyor through hood 102 where warm air is blown across the ferrule to accelerate the cure of the cement. When the brush comes out of the heating hood 102, the cement is completely cured and the rod in addition to setting the clamp for insertion of the brush releases the grip of the clamp on the completed brush so that the brush drops down on to the conveyor belt and is carried off.

It will be understood that it is intended to cover all changes and modifications of the preferred embodiment of the invention herein chosen for the purpose of illustration which do not constitute a departure from the spirit and scope of the invention.

I claim:

1. A device for manufacturing paint brushes of the type which include a ferrule, bristles and a handle united by a substantially solventless cement comprising a conveyor, a drive means for moving the conveyor, a pump positioned adjacent the conveyor for mixing, measuring and dispensing the substantially solventless cement, ferrule carrying means attached to the conveyor for holding the ferrules with the bristles therein so the bristles hang freely from the ferrule and the open end of the ferrule is free of obstructions, and means for coordinating the mixing, measuring and dispensing of the cement by the pump with the positioning of the ferrule holding means with the ferrules therein so the cement is dispensed in a measured quantity only into the ferrules with bristles therein.

2. The structure of claim 1 wherein said drive means is an intermittent drive means so that the ferrule carrying means moves with an intermittent motion, stopping under the pump.

3. The structure of claim 2 wherein the ferrule carrying means include spring loaded jaws which clamp around the ferrules.

4. The structure of claim 3 including means for the opening and setting open the spring loaded jaws to release a completed brush therefrom and ready the jaws for the insertion of another ferrule.

5. The structure of claim 4 including means for inserting the handles into the ferrules without dislodging the bristles.

6. The structure of claim 5 including heating means for heating the ferrules to accelerate the curing of the resinous cement.

7. The structure of claim 4 including means to comress the spring of the spring loaded jaws so the jaws open and release the brush and the spring loaded catch is set to hold the jaws in the open position until the touch responsive pressure plate is contacted.

8. A device for the manufacturing of paint brushes of the type which include a ferrule, bristles and a handle united by a substantially solventless cement comprising a conveyor belt, a number of spring loaded jaws connected at intervals around the conveyor belt for holding ferrules around their exterior in a manner permitting the bristles to hang freely from their ferrules, said jaws each having a touch sensitive spring loaded catch which holds the jaws open until the touch sensitive catch is touched by the ferrule and the jaws close around the ferrule, a pump positioned next to the conveyor for mixing and measuring a resinous cement and then dispensing a measured amount of the resinous cement into the ferrules atop the bristles, drive means for driving the conveyor belt with an intermittent motion so each of the ferrules stop momentarily under the pump to receive the resinous cement, and means for coordinating the mixing, measuring and dispensing of the resinous cement by the pump with the position of the ferrule holding means so that a measured amount of the cement is dispensed only in the ferrules having bristles therein.

9. A system for manufacturing paint brushes of the type which includes a ferrule, bristles and a handle locked together in the ferrule by a hardened composition poured 7 into the ferrule in the form of a substantially solventless pourable liquid comprising means for holding ferrules with bristles therein in a manner not interfering with the insertion of a handle or the pouring of liquid into the ferrule, a conveyor for continuously transporting a number of ferrules so held through a plurality of stations, a pump at the first of said stations which mixes the substantially solventless liquid from a liquid of a proper viscosity for penetration into the bristles with a curing agent for that liquid and then dispenses said substantially solventless liquid in a measured amount into each of the ferrules, and means coordinating the mixing, measuring and dispensing of the liquid by the pump With the position of the ferrule holding means so that the liquid is only dispensed when a ferrule is 15 moved into said first station by said holding means.

10. The structure of claim 9 including means at a second of said stations for inserting handles into the ferrules so that a portion of handle enters the liquid without disturbing the bristles.

11. The structure of claim 9 including heating means at a third of said stations for heating the ferrules to harden the liquid composition.

References Cited in the file of this patent UNITED STATES PATENTS 2,291,240 Landeck et al July 28, 1942 2,314,306 Cave Mar. 16, 1943 2,337,603 Hertzberg Dec. 28, 1943 2,648,861 Hardman et al Aug. 18, 1953 2,664,315 Baumgartner Dec. 29, 1953 2,854,684 Hardman et al Oct. 7, 1958 

1. A DEVICE FOR MANUFACTURING PAINT BRUSHES OF THE TYPE WHICH INCLUDE A FERRULE, BRISTLES AND A HANDLE UNITED BY A SUBSTANTIALLY SOLVENTLESS CEMENT COMPRISING A CONVEYOR, A DRIVE MEANS FOR MOVING THE CONVEYOR, A PUMP POSITIONED ADJACENT THE CONVEYOR FOR MIXING, MEASURING AND DISPENSING THE SUBSTANTIALLY SOLVENTLESS CEMENT, FERRULE CARRYING MEANS ATTACHED TO THE CONVEYOR FOR HOLDING THE FERRULES WITH THE BRISTLES THEREIN SO THE BRISTLES HANG FREELY FROM THE FERRULE AND THE OPEN END OF THE FERRULE IS FREE OF OBSTRUCTIONS, AND MEANS FOR COORDINATING THE MIXING, MEASURING AND DISPENSING OF THE CEMENT BY THE PUMP WITH THE POSITIONING OF THE FERRULE HOLDING MEANS WITH THE FERRULES THEREIN SO THE CEMENT IS DISPENSED IN A MEASURED QUANTITY ONLY INTO THE FERRULES WITH BRISTLES THEREIN. 